|
|
Effect of the currently used plasticizers for concrete hydration temperature
Knotová, Kateřina ; Halas, Vladimír (referee) ; Sedlmajer, Martin (advisor)
Plasticizing and superplasticizing admixtures are the key components of nearly every concrete. These admixtures improve workability of mortar and fresh concrete which lead to facilitation of depositing and compaction. Adding of plasticizers or superplasticizers enables to change properties of fresh and hardened concrete, especially to reduce water-cement ratio, thereby increasing strength and durability of concrete or to improve other properties. The main aim of this thesis is to monitor the effect of plasticizing admixtures and their dosage on the rheology and hydration of concrete with emphasis on the development of hydration temperature. The other goal is to examine their strength qualities. Behaviour of plasticizing admixtures is analysed at first on cement pastes, as simple systems, and then verified on concrete.
|
|
|
Effect of chemical additives on the process hydration temperature of cement pastes
Knotová, Kateřina ; Halas, Vladimír (referee) ; Sedlmajer, Martin (advisor)
Chemical additives, especially plasticizers and super plasticizers, are necessary components of nearly every concrete. These additives improve the workability of grout and concrete mixes thereby reducing vibration intensity during process of compaction. Advantages of these additives are associated with reduction of the amount of gauging water which leads to decrease water-cement ratio, increase strength and durability of concrete, eventually improve other attributes. The aim of this thesis is to observe the effect of plasticizers and their dosage on the rheology and development of hydration temperatures in simpler systems, which are the cement pastes. The thesis also considers compressive, tensile and flexural strength of concrete.
|
|
|
Study of possibilities of reduction of volume changes and development of hydration temperatures in concrete
Pikna, Ondřej ; Ťažký, Tomáš (referee) ; Hela, Rudolf (advisor)
Volume changes are one of the priority characteristics of concrete that plays an important role place mainly in the durability of structures as such. These low volume changes are required especially for structures as: industrial concrete floors, massive structures and waterproof structures. One of the possibilities in reducing these changes is the use of mineral admixtures with suitable grain curve of aggregate. Another possibility is the use of shrinkage reducing admixtures. There can occur problem with efficiency (long term age) with other components of the mixture. Therefore, the effort of this work is to use the avaible processes for maximum reduction of shrinkage and hydration temperatures.
|
|
| |
|
|
Study of possibilities of reduction of volume changes and development of hydration temperatures in concrete
Pikna, Ondřej ; Ťažký, Tomáš (referee) ; Hela, Rudolf (advisor)
Volume changes are one of the priority characteristics of concrete that plays an important role place mainly in the durability of structures as such. These low volume changes are required especially for structures as: industrial concrete floors, massive structures and waterproof structures. One of the possibilities in reducing these changes is the use of mineral admixtures with suitable grain curve of aggregate. Another possibility is the use of shrinkage reducing admixtures. There can occur problem with efficiency (long term age) with other components of the mixture. Therefore, the effort of this work is to use the avaible processes for maximum reduction of shrinkage and hydration temperatures.
|
|
|
Effect of the currently used plasticizers for concrete hydration temperature
Knotová, Kateřina ; Halas, Vladimír (referee) ; Sedlmajer, Martin (advisor)
Plasticizing and superplasticizing admixtures are the key components of nearly every concrete. These admixtures improve workability of mortar and fresh concrete which lead to facilitation of depositing and compaction. Adding of plasticizers or superplasticizers enables to change properties of fresh and hardened concrete, especially to reduce water-cement ratio, thereby increasing strength and durability of concrete or to improve other properties. The main aim of this thesis is to monitor the effect of plasticizing admixtures and their dosage on the rheology and hydration of concrete with emphasis on the development of hydration temperature. The other goal is to examine their strength qualities. Behaviour of plasticizing admixtures is analysed at first on cement pastes, as simple systems, and then verified on concrete.
|
|
| |
|
|
Effect of chemical additives on the process hydration temperature of cement pastes
Knotová, Kateřina ; Halas, Vladimír (referee) ; Sedlmajer, Martin (advisor)
Chemical additives, especially plasticizers and super plasticizers, are necessary components of nearly every concrete. These additives improve the workability of grout and concrete mixes thereby reducing vibration intensity during process of compaction. Advantages of these additives are associated with reduction of the amount of gauging water which leads to decrease water-cement ratio, increase strength and durability of concrete, eventually improve other attributes. The aim of this thesis is to observe the effect of plasticizers and their dosage on the rheology and development of hydration temperatures in simpler systems, which are the cement pastes. The thesis also considers compressive, tensile and flexural strength of concrete.
|
guest ::
